This might be the gnome bug https://bugzilla.gnome.org/show_bug.cgi?id=615853 which has been fixed in gtk2-engines-pixbuf 2.20.1-0ubuntu1
** Bug watch added: GNOME Bug Tracker #615853 https://bugzilla.gnome.org/show_bug.cgi?id=615853 -- Changing volume using media keys or custom keyboard shortcuts on second monitor affects gnome desktop theme https://bugs.launchpad.net/bugs/420702 You received this bug notification because you are a member of Ubuntu Desktop Bugs, which is a bug assignee. -- desktop-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/desktop-bugs
